Grinding machine



July 25, 1933. c. BOOTH 1,919,615

GRINDING MACHINE Filed May 27, 1930 2 Sheets-Sheet 1 gwue'ntoz (Zi/W/Mw/W I ,4 r 1 I 1 V (I m 6 dttouuq July 25, 1933. Q BOOTH 1,919,615

GRINDING MACHINE Filed May 27, 1930 2 Sheets-Sheet 2 Z9 6) ll 9 55 Z5 9' Patented July 1933 UNITED STATES PATENT OFFICE CLEMENT BOOTE OF CINCINNATI, OHIO, ASSIGNOR, BY MFSNE ASSIGNMENTS, TO THE EEALD 'MACHINE COMPANY, OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS GRINDING MACHINE Application filed May 27,

invention is the provision of an improved automatic control mechanism for a machine tool for limiting the stock removal from an individual work piece and efl'ecting relative withdrawal of the tool and the work piece when the latter is reduced to prescribed size. A further object of the present invention is to provide an improved gauging or size determining mechanism applicable to grinding machines or other machine tools or the like which shall be particularly efficient in cooperating with the surface of work pieces being machined to indicate the reduction in size thereof or stock removal therefrom.

Other objects and advantages of the present invention should be readily apparent by reference to the following specification considered in conjunction with the accompanymg drawings forming a part thereof and it will be understood that any modification of the specific structural details hereinafter disclosed may be made within the scope of the appended claims without departing from or exceeding the spirit of the invention.

Figure 1 is a front elevationof an internal grinder having the improvements in question applied thereto.

Figure 2 is a fragmentary view partially in plan and partially in section illustrating the operative position of said mechanism.

Figure 3 is a vertical section as on line 33 of Figure 2 Figure 4 is a section as Figure 3.

Figure 5 is a section through the control mechanism for the size determinator as on the line 55 of Figure'2.

Figure 6 is a fragmentary section through the adjusting mechanism as on line 6-6 of Figure 3, and

Figure 7 is a diagrammatic view illustrating the several control circuits of the machine in their coupled relation to the size determinator. 4

on line 4-4 of pieces of correspond- 1930. Serial No. 456,211.

Figure. 8 is a diagrammatic view showing the application of the gage to internal grindmg.

- Figure 9 is a diagrammatic view showingthe application of the gage to external grindmg.

In the drawings, in which similar characters of reference are employed to denote corresponding' parts throughout the several views,

the numeral 10 designates the bed of a grind-- ing machine having Ways 11 for the reciprocating carriage 12 bearing the grinding wheel spindle 13 of grinding wheel 14. This carri age has dogs 15 engaging with the reversing lever 16 for controlling the back and forth or traversing movement of'the carriage and the grinding wheel. Mounted on the carriage is amotor 17 for actuating the grinding wheel.

Formed on the bed in opposition to the ways 11 are ways 18 for the carriage 19 having a movement in a. direction toward and away from the grinding. wheel to present work thereto or retract work out of operative engagement therewith. This carriage has the dovetailed ways 20 on which is mounted for in and out or transverse feeding movement, a supplemental work supporting or cross feed slide 21. This member 21 in the form illustrated is shown as provided with suitable means for rotatably supporting a work piece for action thereon by the grinding -wheel 14. The particular work supporting means illustrated includes a regulating wheel member 22 in peripheral engagement with the work piece 23 to control the rotation thereof, an opposed pressure roller 24, and an intermediate work rest blade 25. It is to be understood however, that any form of work holding chuck orthe like permitting axial access to the work by the sizing member without interference with the grinding wheel would be equally applicable and utilizable since the particular form of work holding mechanism forms .no essential partof the presentinvention.

The sizing mechanism proper is mounted upon the unit 21, and includes a transversely adjustable bracket 26 adapted to be secured in desired position as by the bolts 27 for general location of the unit on the machine.

Suitable means such as an adjusting screw 28,

- the s'wiveled housing 31 of the feeler unit. A

screw- 32 depending from the trunnion through the spring washer 33 and having nuts 34 urging the washer in the direction of the bracket 26 completes the pivotal connection between the housing and bracket to allow a relative angular adjustment of the parts. This angular adjustment is normally utilized \in fine or accurate positioning of the sizing device with respect to the work piece surface.

To control this angular positioning, housing 31 has a socket as at 35, Fig.6, for yielding or spring pressed plunger 36 engaging the upstanding rib or abutment flange 37 Bin bracket 26. A second lug 38 on the bracket has a threaded aperture'to receive the adjusting screw 39 which engages the housing 31 in opposition to the action of plunger 36 to force the housing inwardly about its pivot. It will thus be seen that the forward position of the housing may besvery accurately determined by screw 39 while the plunger and its actuating spring yieldingly hold the housing forward but permit of its reverse movement in the event of undue strain or urge thereagainst.

The housing has formed in its walls aligned apertures r pectively receiving journal bushings 4 and 41 and cap bushing 42 for the rotatable, longitudinally shiftable feeler spindle 43. This spindle has secured to its forward or inner end the head 44 having the thickness determining finger 45 provided with the off-set feeler point 46, preferably a diamond or like hard wear resisting material.

The operation of the mechanism aforesaid will be apparent by reference to Figures 2 and 8 from'which it will be seen that the feeler point 46 enga es the interior of a work piece at a point pre erably diametrically op posed to the engagement of the grinding wheel 14 therewith inasmuch as this provides maximum clearance space for the feeler device. orresponding engagement between the feeler and work when the inven- "tion is utilized with external grinding is shown in Figure 9, the essential being that the feeler is so mounted that when the work 'piece is reduced to size it may swing about the spindle 43 as an axis and snap past the work, whereby the rotary movement of the spindle will actuate suitable mechanism either indicating that the Work has been reduced to desired size or actually energizing or effecting an energization of mechanism for automatically relatively retracting or separating the work and tool and thus discontinuing the stock removal therefrom.

In this connection it will be noted that preferably the direction of normal oscillation of the feeler is in that of the movement of the work surface engaged thereby so that the frictional drag of the work will tend to urge or retain the feeler in the position of oscillation until the work surface has been out free therefrom rather than having the drag of the work tend to move the feeler,vwith the consequent possible snapping by thereof due to work drag before proper size has been reached. It will be understood that'this feature is of particular importance since a mechanism of the kind herein disclosed is intended for use in precision grinding where the limits of accuracy, as determined by the feeler me-chanism, are to be held within a fractional thousandth of an inch.

The snapping by action of the feeler point 46 is effected b the provision on spindle 43 of an elongate pinion 47 in mesh with rack 48, Fig. 4, on plunger 49 slidable in the housing 31 and upwardly actuated by spring 50, whereby the action of the spring and plunger tend to impart a counter clockwise rotation to the spindle and its associated feeler.

By reference particularly to Fig. 3 it will be noted that the spindle is provided at its rear or outer end with a cam 51 of such formation that when the spindle rotates on snapping by of the feeler, the cam will engage with and raise switch plunger 52 to complete a circuit between contacts 53 and 54 of a controlling circuit 55 including solenoid 56 as diagrammatically illustrated in Figure 7 and as further described in detail in copending application Serial Number 374,556. This sole ber 61 to close the circuit of solenoid 62 con-- trolling valve 63 effecting an actuation of piston 64, which through rack 65 rotates gear 66 and shaft 67 for operation of the work feed clamp and ejection mechanism, including the member 68 indicated in Figure 2. As-the shaft 67 oscillates, it carries with it cam 69 acting on plunger 70 to rock the vertical spindle 71, provided with rock arm 72 coupled by link 73 with an arm on rock shaft74. As shaft 74 oscillates, arm 75 thereon engaged in groove 76 of spindle 43, rearwardly slides or reciprocates the spindle with respect to its supports moving the member 46 out of the plane of the work so that the work piece may be suitably removed by the ejector mechanism and a new work piece substituted. At the same time, arm 77 on shaft 74 engages and depresses plunger 49, reversely oscillating the spindle 43 and placing contact 46 in a depressed position ready for re-engagement with the interior of the newly substituted work piece.

Through additional control mechanism, not shown, solenoid 62 is de-energized and the solenoid 80 energized to reversely shift valve 63 and thus member 64. This movement shifts shaft 67 and cam 69, reversely oscillating shaft 74 to cause projection 46 to enter within the work as indicated in Figure 4, and in the continued movement of 74, arm 77 re leases plunger 49 so that the pressure of spring 50 causes feeler point 46 to" bear against the interior of the work for determination of the thickness thereof. The mech- ,movement of the work wheel until the predetermined stock removal anism as an entirety is now moved to bring the work into operative relation with the grinding wheel and to procure a cross feed toward the grinding allows the feeler to rotate within the work and cause automatic discontinuance of the grinding, and e'ection of the completed work piece as hereto ore described.

It will be noted that the action of cam 69 against plunger 70 and thus through arm 72 and link 7 3 to shaft 74 is positive in its retraction of spindle 43 and reversal of movement of the feeler 46, but that the return action'is res'liently effected by spring 79 so that the gaugi tig member is resiliently returned into engagement with the work piece. It will be understobd that the member 43 is given a sufiicient rotative movement that feeler 46 will be in a position-away from the work as the spindle reenters the rear thereof, and will gradually swing around for engagement therewith as arm 77 moves upward, releasing plunger 49. It will further be understood that plunger 49 may be disposed on either side of the spindle as desired, so that the operative snapping by movement may be either an upward or a downward movement of feeler 46 as may be preferred in the individual instance.

I claim:

1. A work size determining gage including an oscillatable, longitudinal, shiftable spindle, a work feeler point'carried thereby, and adapted to ride on the surface of a Work piece, said spindle having a pinion thereon, a rack member meshing with the pinion, and means for resiliently longitudinally urging the rack member to oscillate the spindle to an amount limited by engagement of the gage point thereof with the .work piece.

2. A Work size determining gage including an oscillatable, longitudinal, shiftable spindle, a. work feeler point carried thereby and adapted to ride on the surface of a wor piece, said spindle having a pinion thereon, a rack member meshing with the pinion, means for resiliently longitudinally urging amount limited by engagement of the gage point thereof with the work piece, a control camcarried by the spindle and slidable there with, and an electric switch member having a portion projecting in the path of the cam,

whereby a control circuit will be completed by oscillation of the cam in one direction,

3. A work size determining gageincluding an oscillatable longitudinally 'shiftable spindle, a work feeler point carried thereb and adapted to ride on the surface of a work piece, said s indle having a pinion thereon, a rack mem er meshing with the pinion, means for resiliently, longitudinally urging the rack member to oscillatethes indle to an amount limited by engagement of the gage point thereof with the work piece, a control cam carried by the spindle and slidable therewith, an electric switch member having a portion projecting in the path of the cam wherecillation of the cam in one direction, means for moving the gage into inoperative posi-' tion comprising a bell crank mechanism having an arm adapted to engage and reversally shift the rack and a second arm inter-engaged with the spindle, whereby on rocking of the bell crank mechanism, depression of the one arm of the bell crank willrock the spindle while the other arm will impartia longitudinal shifting movement thereto.

4. A work size determining-gage including an oscillatable longitudinally shiftable spindle, alwork feeler point carried thereby and adapted to ride on the surface of a work piece said spindle having a pinion thereon, a rack member meshing with the pinion and means for resiliently longitudinally urging the rack member to oscillate the spindle to an amount limited by inner engagement of the gage point thereof with the work piece, a support for the gaging member and means for adjusting the position of the member with respect to the support to vary the effective engagement of its contact point with a work piece.

5 A work size determining ga e mechanism including an oscillatable longitudinally shiftable spindle having a work engaging point, means for yieldingly urging the point into engagement with the work and for effecting a continued oscillation of the spindle when the point moves by the work, and

means for automatically longitudinally shifting the spindle and the point to retract the same from the plane of the work upon said 'shiftable spindle having a work engaging point, means for yieldingly urging the point into engagement with the work and for effecting a continued oscillation of the spindle when the point moves by the Work, and means for automatically longitudinally shifting the 7 A work size determining device for a grindingmachine or the like, including a bracket member adapted to be disposed adjacent the work piece, a spindle longitudinally slidable in the bracket from a retracted position out of the plane of the work piece into a position in alinement with the work piece, said spindle having a feeler projecting to one side of the axis thereof, means for yieldably effecting oscillation of the spindle about its axis to shift the feeler in an arc intersecting the arc of the surface to be engaged thereby, whereby the feeler will snap by the work under the urge of said resilient means, when said arcs become tangent one to the other, and means operative on said snap of the feeler for automatically retracting the feeler out of alinement with the work.

8. A work size determiningdevice for a grinding machine or the like, including a bracket member adapted to be disposed adjacent the work piece, a spindle longitudinally slidable in the bracket from a retracted position out of the plane of the work piece into a position in alinement with the work piece, said spindle having a feeler projecting to one side of'the axis thereof, means for yieldably effecting oscillation of the spindle about its axis to shift the feeler in an arc intersecting the arc of the surface to be engaged thereby, whereby the feeler will snap by the work under the urge of'said resilient means, when said arcs become tangent one to the other, means operative on said snap of the feeler for automatically retracting the feeler out of alinement with the work, and means effective during retraction of the spindle for reversely oscillating the feeler into position for re-engagement with a work piece.

9. A work size determining device for a grinding machine or the like, including a bracket member adapted to bedisposed adjacent the work piece, a spindle longitudinally slidable in the bracket from a retracted position out of the plane of the work piece into a position in a ementwiththe work piece, said spindle having a feeler projecting to one side of the axis thereof, means for yieldably. effecting oscillation of the spindle intersecting the arc of the surface to be engaged thereby, whereby the feeler will snap by the work under the urge of said resilient means, when said arcs become tangent one to the other, means operative on said snap of feeler out of alinement with the work, and means effective during retraction of the spindle for reversely oscillating the feeler into position for re-engagement with a work piece,

5 and means operative to project the spindle about its axis to shift the feeler in an arc the feeler for automatically retracting theintoalinement with a new work piece, while the spindle is maintained in said reversely oscillatable position.

10. In a work size determinin mechanism the combination of a bed, a wor support on the bed, a tool for reducing the work, means for efiecting a relative feed between the tool and work, a work feeler contacting with the work for stopping further feed upon reduction of the Work to the desired size, a housing for the feeler, an adjustable bracket for the housing, means for clamping the housing to the-bracket comprising a trunnion depending from the housing, an aperture in the bracket receiving the trunnion, a clamp screw extending from the trunnion throu h the aperture in the bracket and beyond, 105(- ing means carried by the screw for clamping the bracket and housing to one another, and means for adjusting the housing about the axis of the trunnion including a screw for positively shifting the housing in one direction, and yielding means opposed to the screw for shifting the housing in the other direction.

11. In a work size determining device for a grinding machine or the like the combination of an adjustable bracket adjacent a work piece being operated upon, a housing pivotally supported by the bracket, a feeler projecting from the housing for engagement with the Work, means for locking the housing in adjusted position, and means for adjusting the housing about its pivot comprising a pair of upstanding lugs on the bracket and positioned respectively on opposite sides of the housing, the housing having a socket formed therein in alignment withrone of the In a yielding plun er within the socket an gaging the adjacent lug tending to yieldingly agtuate the bracket, and a stop and adjustingscrew carried by the other lug and engag-- ing the housing for limiting the adjustment of the housing by the plunger.

12. In a device of the class described, the combination with a bed, a grinding wheel rotatably mounted thereon, a Work support for supporting work pieces in operative relation to the grinding wheel, and means for effecting a feeding movement between the grinding wheel and work, of means for controlling the feeding movement, said means comprising an oscillatable longitudinally shiftable spindle having a work engaging point, and means for yieldingly urging the point into engagementwith the work and for effecting an extended oscillation of the spindle when the point moves by the work, and means responsive to said oscillation for automatically shifting the spindle and the work engaging point to retract said spindle and point from the plane of the work, and other means responsive to said oscillation for procuring separation of the grindingwheel from T the work piece. 7

ent 13. In a device of the class described, the

point into engagement with the work and for eifecting an extended oscillation of the spindle when the point moves by the work, and means responsive to said oscillation for energizing an electrical circuit to procure shifting movement of the spindle and point to retract said spindle and point from the plane of the work and to procure separation of the grinding wheel and the work piece.

CLEMENT BOOTH. 

